Seat back and insert

Abstract

Described is a seat back comprising a rear wall bordered by side walls projecting forward from the rear wall. The rear wall and side walls define a cavity in front of the rear wall and between opposing surfaces of the side walls. The seat back comprises an insert disposed at least partially within the cavity which is for supporting the back of a person leaning against the front of the seat back. The seat back and insert are shaped such that when the insert is positioned within the cavity, movement of the insert towards the base of the seat back is restricted.

1 . A seat back, the seat back comprising a rear wall bordered by side walls projecting forward from the rear wall, said rear wall and side walls defining a cavity in front of the rear wall and between opposing surfaces of the side walls, wherein the seat back comprises an insert disposed at least partially within the cavity, said insert for supporting the back of a person leaning against the front of the seat back, wherein the seat back and insert are shaped such that when the insert is positioned within the cavity, movement of the insert towards the base of the seat back is restricted. 
     
     
         2 . A seat back according to  claim 1 , wherein the side walls are part of a perimeter wall projecting forward from the rear wall, said rear wall and perimeter wall defining the cavity in front of the rear wall and between opposing surfaces of the perimeter wall. 
     
     
         3 . A seat back according to  claim 1 , wherein the width of the cavity and the insert tapers from a first width to a second width, wherein the first width is positioned above the second width and wherein the first width is greater than the second width. 
     
     
         4 . A seat back according to  claim 1 , wherein the seat back comprises one or more shaped profiles for mutual engagement with one or more shaped profiles of the insert, wherein said shaped profiles are for restricting downward movement of the insert relative to the seat back when the insert is positioned within the cavity. 
     
     
         5 . A seat back according to  claim 1 , wherein the seat back comprises one or more recesses for engagement with one or more protrusions on the insert and for restricting downward movement of the insert relative to the seat back when the insert is positioned within the cavity. 
     
     
         6 . A seat back according to  claim 1 , wherein the seat back comprises a recess in a forward facing surface thereof for engagement with a protrusion on the insert. 
     
     
         7 . A seat back according to  claim 2 , wherein the seat back comprises a recess in a forward facing surface of the perimeter wall for engagement with a protrusion on the insert. 
     
     
         8 . A seat back according to  claim 1 , wherein the seat back comprises a recess in a forward facing surface of its upper edge for engagement with a protrusion on the insert. 
     
     
         9 . A seat back according to  claim 8 , wherein each side wall comprises an upper part which is sloped from the setback position of the forward facing surface of the upper edge to the forward facing surface of the remainder of each side wall. 
     
     
         10 . A seat back according to  claim 2 , wherein the seat back comprises a recess in a forward facing surface of the upper wall of the perimeter wall for engagement with a protrusion of the insert. 
     
     
         11 . A seat back according to  claim 10 , wherein the forward facing surface of the perimeter wall is sloped from the setback position of the forward facing surface of the upper wall to the forward facing surface of each side wall of the perimeter wall. 
     
     
         12 . A seat back according to  claim 1 , wherein the insert is shaped to fit within the cavity between the side walls and to overlap the forward facing surface of the or an upper edge of the seat back. 
     
     
         13 . A seat back according to  claim 9 , wherein the insert comprises one or more lateral tabs for engagement with the sloped forward facing surface of the perimeter wall or sloped forward facing surface of the side walls. 
     
     
         14 . A seat back according to  claim 1 , wherein the perimeter wall of a lower part of the seat back is substantially semi-circular. 
     
     
         15 . A seat back according to  claim 1 , wherein the lower part of the seat back is substantially semi-circular. 
     
     
         16 . A seat back according to  claim 1 , wherein the depth of the cavity is greater at the base of the seat back than in an upper part of the seat back. 
     
     
         17 . A seat back according to  claim 1 , wherein the base of the cavity is not filled by the insert. 
     
     
         18 . A seat back according to  claim 1 , wherein the insert comprises a recess in its bottom edge such that, when inserted into the cavity, the insert does not extend to the base of the cavity. 
     
     
         19 . A seat comprising a seat back according to  claim 1 . 
     
     
         20 . A row of seats comprising a plurality of seats according to  claim 19 .